In the development of textile looms, one deterent to operating looms at higher speed has always been the fact that the weft had to be carried back and forth by a flying shuttle. The mass of this shuttle must be accelerated to high speed as it passes from one side of the loom to the other and decelerated at the other end, after which it must be re-accelerated and decelerated again in returning to its original position. This has definitely inhibited higher speed looms. Once the mass of the shuttle has been reduced to as low a value as is practical, the only way that the shuttle passage through the loom shed can be speeded up is by imparting larger amounts of energy to it at the end of its travel. In the conventional flying shuttle loom, this energy has been imparted by the picker stick. The more energy the picker stick imparts to the shuttle the greater the noise; various government agencies have not only restricted the amount of noise that can exist in a loom room of a textile factory, but have taken positive steps to reduce the noise. Since speeding up the loom has been definitely limited in this way, because of noise and other factors, such as wear on the equipment, other methods of transferring the weft back and forth through the shed have been seriously considered. One method of weft transfer that thas had some success is the use of thin, cantilevered rods or rapiers which move halfway across the shed and transfer the weft end in the middle of the loom. However, the mechanism for producing rapier action is quite intricate and expensive, so that many mill owners would prefer to operate with their old, slow-operating looms rather than convert to the expensive high-speed rapier looms. Another factor holding up the introduction of the rapier-type loom has been fact that the intricate mechanism necessary to drive the repiers tends to wear out; the replacement parts are expensive and there is also a degree of expensive down-time while the repair is being made. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a drive mechanism for rapier-type looms, which mechanism is simple in construction, inexpensive to manufacture, and is capable of a long life of useful service with a minimum of maintenance.
Another object of this invention is the provision of a drive mechanism that can be used to convert a conventional flying-shuttle loom to a rapier-type loom.
A further object of the present invention is the provision of a drive mechanism for a rapier-type loom in which the major parts that are subject to wear are readily replaceable.
It is another object of the instant invention to provide a drive mechanism for a loom of the rapier-type in which each part is simple and inexpensive and in which each part can be easily replaced without complete dis-assembly of the mechanism.
A still further object of the invention is the provision of a drive mechanism for a rapier-type loom which is low in power consumption.
It is a further object of the invention to provide a drive mechanism for the rapiers of a shuttleless loom in which an increased fabric width is possible for a given loom width.
A further object of the invention is the provision of a single drive unit for a double rapier system which balances out many of the inertia forces at reversal.
Another object of the invention is the provision of a loom with a single drive, double rapier system in which is eliminated any lost motion overide at reversal where the pick-up and yarn transfers occur.
It is a still further object of the present invention to provide a drive mechanism for a rapier-type shuttleless loom, which mechanism introduces a dwell in the rapier movement at the outer limits of rapier path, during which dwell both the heddle action and the weft gripper action can take place in a leisurely manner.
Another object of the invention is the provision of a loom which is relatively free of noise and shock at all times during the weaving cycle, so that it operates not only with less noise and less wear on the parts, but the fabric generated is of better quality.
Another object of the invention is the provision of a shuttleless loom having reciprocating rapiers for transferring the weft, wherein the rapiers do not move continuously, but remain in a fixed position just outside of the web for a portion of the weaving cycle when the beat-up action takes place and the weft pickup takes place, thus resulting in a shorter weft length with better control of the weft and, therefore, better quality of cloth, as well as allowing a simpler and more reliable yarn pickup mechanism.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.